1. Field of the Invention
The present invention relates generally to audio signal processing and more specifically to automated tools for applications such as speech therapy and language instruction.
2. Description of the Related Art
Intonation is an important aspect of speech, especially in the context of spoken language. Intonation is associated with a speech utterance and it represents features of speech such as form (e.g., statement, question, exclamation), emphasis (a word in a phrase or part of word can be emphasized), tone, etc.
The benefits of intonation variation as an aid to speech therapy are known. In a typical case, a speech therapist listens to the live or recorded attempts of a student to pronounce test words or phrases. In the event the student has difficulty pronouncing one or more words, the therapist identifies and stresses the mispronounced words for the student by repeating the word to the student with an exaggerated intonation in which the pitch contour of the word or one or more parts of the word is modified. Generally, the student will make another attempt to properly pronounce the word. The process typically would be repeated as necessary until the therapist is satisfied with the student's pronunciation of the target word. Continued failure to properly pronounce the word could invoke progressively more severe intonation variations for added emphasis.
Automated tools for general speech therapy are known in the art. The automated tools currently available for speech therapy are typically software programs running on general-purpose computers. Coupled to the computer is a device, such as a video monitor or speaker, for presenting one or more test words or phrases to a student. Test words or phrases are displayed to the student on the monitor or played through the speaker. The student speaks the test words or phrases. An input device, such as a microphone, captures the spoken words or phrases of the student and records them for later analysis by an instructor and/or scores them on such components as phoneme pronunciation, intonation, duration, overall speaking rate, and voicing. These tools, however, do not provide a mechanism for automated intonation variation as an aid to speech therapy.